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      <td class="header">&nbsp; Import Sentinel-1 </td>
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<h3>Import Sentinel-1&nbsp;Product</h3>

<p>
</p>

<p class="MsoNormal"><b style="">Operational: </b>S1A
2014-04-03 to present, S1B 2016-04-25 to present</p>

<p class="MsoNormal"><b style="">Frequency Band:</b>
C-band</p>

<p class="MsoNormal"><b style="">Acquisition Modes:</b><span style="">&nbsp;
</span>Interferometric Wideswath (IW), Extra
Wideswath (EW), Stripmap (SM) and Wave (WV)</p>

<p class="MsoNormal"><b style="">Product Types:</b>
Single Look Complex (SLC), Ground Range Detected (GRD), Ocean (OCN)</p>

<ul>

  <li>Level-1 SLC for IW, EW, SM modes</li>
  <li>Level-1 GRD for IW, EW, SM modes</li>
  <li>Level-2 OCN for IW, EW, SM, WV modes</li>
</ul>

<p class="MsoNormal"><span style="">SENTINEL data
products are distributed using a SENTINEL-specific variation of the
Standard
Archive Format for Europe (SAFE) format specification. The SAFE format
has been
designed to act as a common format for archiving and conveying data
within ESA
Earth Observation archiving facilities.&nbsp;</span></p>

<p class="MsoNormal"><span style="">The SENTINEL-SAFE
format wraps a folder containing image data in a binary data format and
product
metadata in XML. This flexibility allows the format to be scalable
enough to
represent all levels of SENTINEL products.</span></p>

<p class="MsoNormal"><span style="">A SENTINEL product
refers to a directory folder that contains a collection of information.
It
includes:</span></p>

<ul style="margin-top: 0cm;" type="disc">

  <li class="MsoNormal" style=""><span style="">a 'manifest.safe' file
which holds the general product information in XML</span></li>
  <li class="MsoNormal" style=""><span style="">subfolders for
measurement datasets containing image data in various binary formats</span></li>
  <li class="MsoNormal" style=""><span style="">a preview folder
containing 'quicklooks' in PNG format, Google Earth overlays in KML
format and HTML preview files</span></li>
  <li class="MsoNormal" style=""><span style="">an annotation folder
containing the product metadata in XML as well as calibration data</span></li>
  <li class="MsoNormal" style=""><span style="">a support folder
containing the XML schemes describing the product XML.</span></li>
</ul>

<p class="MsoNormal"><span style="">The manifest file
is an XML file containing the mandatory product metadata common to all
SENTINEL-1
products.</span></p>

<p class="MsoNormal"><span style="">Annotated data sets
contain metadata describing the properties and characteristics of the
measurement data or how they were generated. For each band of data
there is a
product annotation data set that contains metadata describing the main
characteristics corresponding to that band such as the state of the
platform
during acquisition, image properties, polarisation, Doppler
information, swath
merging and geographic location. Calibration annotations contain
calibration
information and the beta nought, sigma nought, gamma and digital number
look-up
tables that can be used for absolute product calibration. Noise data
annotations contain the estimated thermal noise look-up tables.
Annotated data
sets are provided in XML format. Level-2 products do not contain
annotation
data sets as all product metadata is contained within the netCDF
product file.</span></p>

<p class="MsoNormal"><span style="">In the preview
folder, quicklook data sets are power detected, averaged and decimated
to
produce a lower resolution version of the image. Single polarisation
products
are represented with a greyscale image. Dual polarisation products are
represented by a single composite colour image in RGB with the red
channel (R)
representing the first polarisation, the green channel (G) represents
the
second polarisation and the blue channel (B) represents an average of
the
absolute values of the two polarisations. Level-2 OCN products do not
contain
quicklooks.</span></p>

<p class="MsoNormal"><span style="">Representation data
sets found in the support folder contain information about the format
or syntax
of the measurement and annotated data sets and can be used to validate
and
exploit these data. Representation data sets are provided as XML
schemas.</span></p>

<p class="MsoNormal"><span style="">Measurement data
sets contain the binary information of the actual acquired or processed
data.
For Level-0 this is the instrument data, for Level-1 it is the
processed images
and for Level-2 it is the derived data. There is one measurement data
set per
polarisation and per swath. TOPSAR SLC products contain one complex
measurement
dataset in GeoTIFF format per swath per polarisation. Level-1 GRD
products
contain one detected measurement dataset in GeoTIFF format per
polarisation.</span></p>

<p class="MsoNormal"><span style="">Measurement data
sets are provided in GeoTIFF format for Level-1 products and netCDF
format for
Level-2 products. The Level-2 OCN products in netCDF format include
both the
annotation and measurement datasets described as netCDF attributes,
dimensions
and variables in one self-describing, self-contained file.</span></p>

<p class="MsoNormal"><b><u><span style="">Level 1 SLC</span></u></b><span style="">: </span><span style="">L1 Single Look
Complex (SLC) products consists of focused SAR data geo-referenced
using orbit
and attitude data from the satellite and provided in zero-Doppler
slant-range
geometry. The products include the full TX signal bandwidth and uses
complex
samples preserving the phase information. Stripmap SLCs contain one
image per swath
and polarization band. SM contains 1 image per polarization band. IW,
having 3
swaths, has 3 images in single pol and 6 images for dual pol. EW,
having 5
swaths, has 5 image for single pol and 10 image for dual pol. Each
sub-swath
consists of a series of bursts. Each burst has been processed as a
separate SLC
image.</span></p>

<p class="MsoNormal"><b><u><span style="">Level 1 GRD</span></u></b><b><span style="">: </span></b><span style="">L1 Ground Range Detected (GRD)
products
consist of focused SAR data that has been projected to ground range
using an
Earth ellipsoid model, detected and multilooked. Phase information is
lost.</span><span style=""> </span><span style="">GRD products
can be in one of three resolutions Full Resolution (FR), High
Resolution (HR),
or Medium Resolution (MR). L1 GRD products come in MR and HR for IW and
EW
modes, MR for WV mode and MR, HR and FR or SM mode.</span></p>

<p class="MsoNormal"><b><u><span style="">Level 2 OCN</span></u></b><u><span style="">: </span></u><span style="">The L2 Ocean
products may include Ocean WInd field (OWI), Ocean SWell spectra (OSW)
and
surface Radial VeLocity (RVL) information derived from the SAR data.
The OWI is
a ground range gridded estimate of the surface wind speed and direction
at 10m
above the surface derived from the L1 GRD images of SM, IW or EW modes.
The OSW
is a two-dimensional ocean surface swell spectra and also includes an
estimate
of the wind speed and direction per swell spectrum. The OSW is
generated from
SM and WV modes only. For SM, there are multiple spectras derived from
the L1
SLC image. For WV, there is one spectra per vignette. The RVL is a
ground range
gridded difference between the measured L2 Doppler grid and the L1
calculated
geometrical Doppler.</span></p>

<p class="MsoNormal"><b style="">Polarizations:</b> Dual
Pol VV+VH or HH+HV</p>

<p class="MsoNormal"><b style="">Primary metadata
file: </b>manifest.safe</p>

<p class="MsoNormal"><b style="">Opening products:</b>
Products can be opened by selecting the manifest.safe file. Opening
zipped
products (*.zip) directly is also supported.</p>

<p class="MsoNormal"><b style="">Further Information: </b></p>

<p class="MsoNormal"><a href="https://sentinel.esa.int/web/sentinel/user-guides/sentinel-1-sar">https://sentinel.esa.int/web/sentinel/user-guides/sentinel-1-sar</a></p>

<p class="MsoNormal"><a href="https://directory.eoportal.org/web/eoportal/satellite-missions/c-missions/copernicus-sentinel-1">https://directory.eoportal.org/web/eoportal/satellite-missions/c-missions/copernicus-sentinel-1</a></p>

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